A system is known, for example, from U.S. Pat. No. 5,694,026, which discloses a turbine that is mechanically directly connected to a generator, which in turn is connected via a converter and a transformer to a power supply grid. No mechanical gear is disposed between the turbine and the generator. In the generator operation, the turbine is supplied with fuel, so that the generator is driven by the turbine and thus generates electrical power. This electrical power is fed via the converter and the transformer into the power supply grid.
To start the turbine from the standstill, the generator is operated as a motor, wherein electrical power is supplied from the grid via the transformer and the converter to the generator in order to start the generator rotation. The turbine is accelerated in this way to a desired rotational speed.